Imaging the valley and orbital Hall effect in monolayer <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mi mathvariant="normal">MoS</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:math>
Fei Xue, Vivek Amin, Paul M. Haney
Abstract
The topological properties of a material's electronic structure are encoded in its Berry curvature, a quantity which is intimately related to the transverse electrical conductivity. In transition metal dichalcogenides with broken inversion symmetry, the nonzero Berry curvature results in a valley Hall effect. In this Rapid Communication we identify a previously unrecognized consequence of Berry curvature in these materials: an electric-field-induced change in the electrons' charge density orientation. We use first-principles calculations to show that measurements of the electric-field-induced change in the charge density or local density of states in ${\mathrm{MoS}}_{2}$ can be used to measure its energy-dependent valley and orbital Hall conductivity.